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The storm called Roke weakened from a powerful typhoon to a tropical storm Wednesday, but death toll continues to rise in Japan.

There have been seven deaths in six prefectures, stretching from Nagasaki in the south to Iwate in the north, official sources told CNN. Authorities say five people are missing but they expect that number to rise when local governments re-open Thursday.

After making landfall Wednesday, Roke lashed some areas with heavy rainfall and brought more woe to a nation already trying to recover from a natural disaster.

The center of Typhoon Roke hit near Hamamatsu city, according to the Japan Meteorological Agency.

It had sustained winds of up to 167 kph (103 mph) Wednesday morning.

The powerful storm comes as Japan is still recovering from the devastating earthquake and tsunami that struck in March, killing more than 15,000 people.

The typhoon may affect Tokyo Electric Power Co.'s Fukushima Daiichi plant, which went into a nuclear crisis after the March disaster.

TEPCO officials said they had outdoor construction canceled at the plant. There were also concerns about whether a strong downpour could wash radiation-contaminated waters out of the plant.

At one point before the storm made landfall, about 1 million people were urged to evacuate from vulnerable areas as heavy rain pounded central and western Japan.

Some downpours came up to 50 millimeters (2 inches) an hour, and some regions received more than 450 millimeters (17 inches) over a day, according to Japanese public broadcaster NHK.

Four people died in Nagoya, including a 66-year-old man who fell from a roof Tuesday while trying to fix a duct, authorities said.

Three others were missing in Gifu prefecture, authorities said.

Several flights toward the Kyushu and Shikoku areas were canceled, transportation officials said. Some passenger trains were not running Wednesday in central and southern Japan.

The storm had also disrupted operations at several Nissan plants, officials said.